Evaluation of an Air Cleaning Device Equipped with Filtration and UV: Comparison of Removal Efficiency on Particulate Matter and Viable Airborne Bacteria in the Inlet and Treated Air

• Published in: International journal of environmental research and public health 2022-12, Vol.19 (23), p.16135
• Main Authors: Li, Peiyang, Koziel, Jacek A, Macedo, Nubia, Zimmerman, Jeffrey J, Wrzesinski, Danielle, Sobotka, Erin, Balderas, Mateo, Walz, William B, Paris, Reid Vincent, Lee, Myeongseong, Liu, Dongjie, Yedilbayev, Bauyrzhan, Ramirez, Brett C, Jenks, William S
• Format: Article
• Language: English
• Subjects: Air flow; Air Pollutants - analysis; Air Pollution, Indoor - analysis; Air Pollution, Indoor - prevention & control; Air quality; Airborne bacteria; Airborne microorganisms; Airborne particulates; Bacteria; Cleaning; Coronaviruses; COVID-19; COVID-19 - prevention & control; Disease transmission; Environmental Monitoring; Filtration; Flow velocity; Health risks; Humans; Indoor air pollution; Indoor environments; Infectious diseases; Low flow; Pandemics; Particle Size; Particulate emissions; Particulate matter; Particulate Matter - analysis; Particulates; Pollutants; Public health; Respiratory Aerosols and Droplets; Ultraviolet radiation; Viruses
• ISSN: 1660-4601; 1661-7827; 1660-4601
• DOI: 10.3390/ijerph192316135

Since the COVID-19 pandemic, improving indoor air quality (IAQ) has become vital for the public as COVID-19 and other infectious diseases can transmit via inhalable aerosols. Air cleaning devices with filtration and targeted pollutant treatment capabilities can help improve IAQ. However, only a few filtration/UV devices have been formally tested for their effectiveness, and little data is publicly available and UV doses comparable. In this research, we upgraded a particulate matter (PM) air filtration prototype by adding UV-C (germicidal) light. We developed realistic UV dose metrics for fast-moving air and selected performance scenarios to quantify the mitigation effect on viable airborne bacteria and PM. The targeted PM included total suspended particulate (TSP) and a coarse-to-fine range sized at PM , PM , PM , and PM . The PM and viable airborne bacteria concentrations were compared between the inlet and outlet of the prototype at 0.5 and 1.0 m /s (low and high) air flow modes. The upgraded prototype inactivated nearly 100% of viable airborne bacteria and removed up to 97% of TSP, 91% of PM , 87% of PM , 87% of PM , and 88% of PM . The performance in the low flow rate mode was generally better than in the high flow rate mode. The combination of filtration and UV-C treatment provided 'double-barrier' assurance for air purification and lowered the risk of spreading infectious micro-organisms.